High-Performance Liquid Chromatography for Determination of N-Nitrosodimethylamine in Water
High-performance liquid chromatography (HPLC) was applied for aqueous determination of Nnitrosodimethylamine (NDMA). A fluorescence derivatization technique was adopted to enhance detection using HPLC. Derivatization with dansyl chloride was optimized for excitation and emission wavelengths (340 and 530 nm, respectively), pH (9-12), and concentration of dansyl chloride (500 mg/L). An instrumental detection limit of 0.1 ng NDMA using a fluorescence detector was achieved. The NDMA in aqueous samples was extracted by continuous solid-phase extraction using 1.5 g Ambersorb 572. NDMA detection could be lowered to a concentration of 10 ng/L in both water and wastewater samples. The chromatographic peak for NDMA was distinct without interference from the complex matrix of wastewater effluents. Such selectivity of the HPLC method for NDMA determination is necessary for wastewater samples.